Ruis (ᚏ) is the fifteenth letter of the Ogham alphabet, derived from ''ruise'' " red" or "reddening". The kennings refer to the reddening of the face caused by intense emotion, and medieval glossators also refer to the practice of reddening the cheeks with the juice of plants. Its Proto-Indo-European root was
''h₁reudʰ-''
'red'. Its phonetic value is

Bríatharogam

In the medieval kennings, called '' Bríatharogaim'' or ''Word Ogham'' the verses associated with ''ruis'' are: - "most intense blushing" in the ''Bríatharogam'' ''Morann mic Moín'' - "reddening of faces" in the ''Bríatharogam'' ''Mac ind Óc'' - "glow of anger" in the ''Bríatharogam'' ''Con'' ''Culainn''.

References

Ogham letters {{writingsystem-stub